32 plates are described in the text, also listed in the atlas, but only 23 were issued in this edition

"The joint committee of the Library of Congress entered into an engagement with the undersigned, in 1851, to prepare the report upon the herpetological collections made by the United States exploring expedition ... He was permitted to associate Dr. Girard with him in its execution; by whom the determinations and descriptions have been made, the drawings overlooked, and the work carried through the press.--S. F. Baird."--Introd

"The book was done entirely by Dr. Charles Girard, but ... his name was not allowed to appear on the title-page by the naval authorities having the matter in charge, who insisted in publishing this book under the name of Professor Baird, to whom the original contract was given out."--G. B. Goode. The published writings of Dr. Charles Girard, 1891, p. 50